Automatic piloting device



Nov. 5, 1935. CONSTANTIN 2,020,105

AUTOMATIC PILOTING DEVICE Filed Sept. 15, 1934 3 Sheets-Sheet 1 Nov. 5,1935. CONSTANTIN 0 AUTOMATIC PILOTING DEVICE Filed Sept. 15, 1934 3Sheets-Sheet 2 Nov. 5, 1935. cON$TANT|N 2,020,105

AUTOMATIC PILOTING DEVICE Filed Sept. 15, 1934 3 Sheets-Sheet 3 PatentedNov. 5, 1935 UNITED STATES AUTOMATIC PILOTING DEVICE Louis Constantin,Paris, France Application September 15, 1984, Serial No. 744,250 InFrance September 19, 1938 Claims. (Cl. 244-29) The object of the presentinvention is to provide an automatic piloting device capable of bothautomatically righting the airplane laterally about its fore and aftaxis and keeping said airplane on the desired course, said device beingapplicable also to airships, submarines and tor- Ihe device according tothe present invention 0 is characterized by the combination of awindvane, preferably a balanced wind-vane, for instance of theConstantin type, adapted automatically to right the airplane laterallyabout its fore and aft axisand controlling either the rudder or theailerons, with means, themselves controlled by any guiding apparatus(radiocompass, tele-compass, etc.), for producing successive alternatinglateral dissymmetries of the airplane, such as a dissymmetry of thewindvane with respect to the airplane, a dissymmetrical position of theailerons, the increase or the reduction of one wing slot, the increaseor the reduction of the lateral resistance on one side, a displacementof the gas throttle of one lateral engine in a multi-engined plane, etc.

But said means do not act directly on the rudder for correctinginstantaneous modifications of the course, the dissymmetry thus producedbeing maintained until a certain angle of the fore and aft axis of theairplane with the correct course has been reached and being thenreplaced by a dissymmetry in the opposite direction.

Furthermore these alternating etries always remain equal to themselveson either side of the median plane of the airplane and their valueremains wholly independent of the quantitative importance of thedeviations from the correct course that are to be corrected.

Every time it has been desired to automatically maintain a vehiclemoving in a fluid on a given course, the rudder of this vehicle wasdirectly subjected to the action of a guiding apparatus, such forinstance as a gyroscope, directly opposing any instantaneous variationof the course and acting quantitatively as a function of the importanceof these variations.

There is another way of obtaining the same result. It sufllces toprovide a wind-vane, preferably a Constantin wind-vane, forautomatically righting of the airplane laterally about its fore and aftaxis and to cause the mean course of the airplane to be deflected in theproper direction by producing successive and alternating slight lateraldissymmetries of a uniform value of the airplane structure about itslongitudinal plane of symmetry. These,

tries will be controlled by thegmding apparatus and will be maintained,without any direct action of the rudder, as long as it will benecessary.

The correct position will be overreached every time and this will resultin producing a series of 5 alternating variations of the true course ofthe airplane on either side of the mean course thereof which, in pointof fact, is the desired course, without the stability of the airplanebeing impaired, owing to the correcting action 10 of the wind-vane.

Preferred embodiments of the present invention will be hereinafterdescribed with reference to the accompanying drawings, given merely byway of example, and in which: 1

Fig. 1 is a diagrammatical view of a device according to the presentinvention;

Fig. 2 shows a switch device which makes it possible to pass from adirecting system to another one;

Fig. 3 relates to a modification and diagrammatically shows an airplanefitted with this modification;

Fig. 4 is a detail view of this modification.

In the embodiment of Fig. l, a Constantin 9,5 wind-vane l acts on therudder 5 through levers 2 and 0 and connecting rod 0. It thus rights theairplane laterally about its fore and aft axis, but at the cost of somedeviations from they course. But as the mean course is always'sub- 30stantially at right angles to the side 0 of the trapezoidal structurethat constitutes one of the parts of the wind-vane, it shall suilice tosuitably control the position of this side 6 for correcting all thesedeviations when they take place.

For this purpose. the axis of articulation I is pivotaliy mounted in ajournal 1 rigid with the airplane and the side 6 of the jointedtrapezoidal structure of the wind-vane is prolonged and op erativelyconnected with the device that will be 0 hereinafter described.

A gyroscope 0 for instance, the support 0" of which is capable ofoscillating about vertical axis 9, is adapted to bring into electricalconnection, through lever I0, contact II with either of contests i2 andit. Contact II is electrically connected with one of the brushes of anindependent excitation direct current motor I. Contact I! is connectedwith the positive terminal of a mat battery of accumulators II andcontact I0 is connected with the negative terminal of a second batteryof accumulators 22.

On the other hand, motor l0, when rotating in. one direction or theopposite one, causes a nut i0 to move forward or backward through theinu being moved toward the right hand side, will leave contact 2| andwhen element l shall have been moved through a predetermined angle thecurrent will be switched on and the motor will stop. However, thecorrection performed by the 'wind-vane will remain eilective until theairmaximum deviation of say one or two degrees,

thatistosaymoreaccuratelythancouldbeobtained with the best pilot.

In the preceding description, it has been assumed that the directing orguiding organ was a gyroscope. But of course many other directing organsmight be employed, such as a telecompass, a radio-compass, a radioelectric beacon, an electro-magnetic cable, etc.

Besides it may be advantageous to guide the airplane on the correctcourse by means of several directing organs employed successively.

Forthispurposelmaymakeuseoiaswitch.

Three conducting rings 23, I4 and (Fig. 2) are electrically connectedwith one of the terminalsoi motor H, the negative terminal of battery 22and the positive terminal of battery 2| respectively. Two contacts I!and I3, disposed concentrically and at the proper interval, areelectrically connected with contacts I I and I3 of Fig. 1, which in Fig.2 are shown in plan view, respectively. An insulating support 26,capable of turning about axis 3|, carries tour brushes 21, ll, 29 and 30electrically connected two by two. Brushes 21 and I! slide along rings24 and II while brushes 28 and it slide along contacts W and II. Underthese conditions, the airplanewillbecontrolledbygyroscope I, asaboveexplained with reference to Fig. l. A system aosonos I pass. etc.shifting from one guiding sysone will be obtained by,merely 5' tom tooperating-the switch.

In'tho modification oi the automatic piloing apparatus shown ln l"igs. 3and 4, the Constantin wind-vane ll controls the rudder 42 oftheairplauethroughatransmission ll. Itism known that it thusmaintains'lsteral equilibrium by preventing sideslipping. 0n the otherhand, isatelecompassrepeatingdialandpointer ll constantly indicates themagnetic north. it is another repeating dial, but which has the 101-lowing characteristics: Pointer 41, which is connected with pointer llthrough a flexible shaft or any other transmission, not shown in thedraw ings, and which rotates at the same rate aspointerll,can-beflxedonits shaitsoastcmakeany go desired angle with thispointer ll. This pointer 41 further carries two brushes It and Itelectrically connected together so asto be capable oi electricallyconnecting a static-nary circular contact II with contact I, disposed inthe fore as andaitplaneoitheairplane. Thethirddial. It carries a pointerII which is caused by a mechanical device, not shown in the drawings, toturn for instance 90 times quicker than pointer 41. This pointer 53carries two brushes 54 and It ll electrically connected together andadapted to connect together circular contact 58, itself constantlyconnected with contact 5i, with either of contacts 51 and 58.Furthermore, this pointer 53 can always be brought back to the zero asposition shown in Fig. 4, by being suitably keyed on its axis. Contact51 is electrically connected with the negative terminal of battery 59and contact 58 is electrically connected with the positive terminal ofthe same battery.

A direct current electric motor BI having a separate excitation elementBI is connected on the one hand with contact and on the other hand withbrush '2, which is itself rigid with nut 83, driven by motor 80 throughthe medium is of endless screw 84. "Nut 63 controls the position of theailerons 65 through lever 66, connecting rod 6] and bevel gears 68.Finally, two contacts." and II are electrically connected with therespective positive and negative terminals of 50 battery ll. Acircuitbreaker II serves to disconnect the battery.

The device above described operates in the following manner:

Let it be supposed that it be desired to follow a course making anangle01' 45 on the east side oi the magnetic meridian. Pointer 41 will befixed in a position making an angle of 45 with respect to pointer 45 onthe east side thereof and circuit breaker II will be closed. 0! coursemotor 60 remains stationary. But, as it will be hereinalter explained,brush B2 is already either on contact is or on contact 10. It will beassumed that brush 2 is on contact ID. The ailerons are then 05 in aposition that corresponds to the airplanenowchangesandtheairplanekeepsturning If it is desired to change thecourse, it sumces to open circuit breaker I I and to modify the anglebetween pointers n and a, after which circuit breaker ll isagainclosed.Thiswillcausethe airplanetotm-nuntilitisintheproperdirection. Pointer 88is brought back into the aero position attherighttimeandthetraiectoryoftheairplane will resume its slowoscillations on either side of the desired direction.

By suitablychoosing the dimensions of contacts II, I! andII,itwillbepossibleto obtainthemost advantageous amplitude for theseoscillations.

Polnterlimaybeapartofanyknwl zillding apparatus (telecompass, gyroscope,radio-compass, etc.) provided with a repeater.

What I claim is:

1. An automatic piloting system for a craft moving in a fluid, whichcomprises, in combination, at least one control surface movably carriedby said craft for steering it, a wind-vane operative by reaction saidfluid thereon to actuate said control surface for automatically rightingsaid craft laterally about its fore and aft axis, means for producingsuccessive and opposite dissymmetries of said craft with reference toits longitudinal plane of symmetry},1 and meansth forlr3; versing thetry w enever e ange said longitudinal plane with a predetermined courseequals aigiven value.

2. An automatic piloting system for an airplane, which comprises, incombination, a rudder for steering said airplane, a wind-vane operativeby reaction of the relative wind thereon to actuate said rudder forautomatically righting said airplane laterally about its fore and aftaxis, means for producing successive and opposite equal dimymmetriesofsaid airplane with reference to its longitudinal plane of symmetry, andmeans for reversing the dissymmetry whenever tlm angle of saidlongitudinal plane with a predetermined course equals a given value.

3. An automatic piloting system for an airplane, which comprises, incombination, a rudder for steering said airplane, a wind-vane operativeby reaction of the relative wind thereon to actuate said rudder forautomatically righting said /airplane laterally about its fore and aftaxis, means for producing equal and opposite successive dissymmetries ofthe structure of said airplane with reference to its longitudinal planeof symmetry, a servo-motor for operating the last mentioned means, meansfor automatically starting said servo-motor for a time suilicient foroperating said last mentioned means whenever the angle of saidlongitudinal plane of symmetry with a given course becomes'equal to apredetermined value, and means, operative by said servo-motor, forreversing the direction of running of said servo-motor at the end ofeach period of rlmning thereof in either direction.

4. An automatic piloting system for an airsaid airplane laterally aboutits fore and aft axis, 25

. a plane, which comprises, in combination, a rudder for steering saidairplane, a wind-vane operative byireaction of the relative wind thereonto actuate" said rudder for automatically righting said airplanelaterally about its fore and aft axis, 5

means-(for producing equal. and opposite successive -etries of thestructure otsaid airc with reference to its longitudinal plane ofsymmetry, a reversible electric servo-motor for operating the lastmentioned means, means for automatically closing the circuit of saidservomotor for a time sumcient for operating said last mentioned meanswhenever the angle of said longitudinal plane of symmetry with a givencourse becomes equal to a predetermined value, and a switch -operativeby said servo-motor for reversing the direction of the current flowingthrough said electric motor at the end of each period of running thereofin either direction.

5. An automatic piloting system for an airplane, which comprises, incombination, a rudder for steering said airplane, a wind-vane operativeby reaction ofthe relative wind thereon to actuate said rudder forautomatically righting means for producing equal and opposite succesaivedissymmetries of the structure of said airplane with respect to itslongitudinal plane of a symmetry, a servo-motor for operating the lastmentioned means, an apparatus, including at 80 least one element capableof remaining constantly in the same relative position with respect to agiven course, for automatically starting said servo-motor for a timesufllcient for operating said last mentioned means whenever the angle 86between said element and said plane of symmetry of the airplane becomesequal to a predetermlned value, andmeans, operative by said servo-motor,for reversing the direction of running of said motor at the end of eachperiod 01' 40 working thereof in either direction. 6. An automaticpiloting system for an airplane, which comprises, in combination, arudder for steering said airplane, a wind-vane operative by reaction ofthe relative wind thereon to actu- I ate said rudder for automaticallyrighting said airplane laterally about its fore and aft axis, means forproducing equal and opposite successive dlssymmetries of the structureof said airplane with respect to its longitudinal plane of .0 symmetry,a servo-motor for operating the last mentioned means, a plurality ofapparatus, including each one element capable of remaining constantly inthe same relative position with respect to a given course, each adaptedto auto- 88 matically start said servo-motor for a time suiiicient foroperating said last mentioned means whenever the angle between saidelement andsaid plane of symmetry of the airplane becomes equal to apredetermined value, switching means 00 for connecting either of theseapparatus with said motor, and means, operative by said servomotor, forreversing the direction of running of said servo-motor at the end ofeach period of working thereof in either direction.

'I. An automatic piloting system for an airplane, which comprises, incombination, a rudder for steering said airplane, a wind-vane operativeby reaction of the relative wind thereon to actuate said rudder forautomatically righting said airplane laterally about its fore and aftaxis. means for producing equal and opposite successive dissymmetries ofthe structure of said airplane with reference to its longitudinal planeof symmetry, a servo-motor for operating the last 16 4 e *Qmios I p 1mentioned means, a first pointer capable of reto automaticeiiy startssid servo-motor for a mnining constantly in the same relative positiontime suiiieient tor operating said last mentioned with respect to agiven course. a second pointer means whenever the'an le between saidelement operatively connected with the iirst mentioned and said plane oisymmetry of the airplane be- }5 one so as to rotate together with it butsoarcomes equal equaito a predetermined value, and

ranged that its relative position with respect to means, operative byacid servo-motor, for resaid first mentioned pointer can be modiversin:the direction of running 01' said motor fled, a third mint er,operativeiy connected at the end 0! each period of working thereof inwiththesecondmentionedonesoastorotateat eitherdirection. m a higheranz'ular speed. contacts adapted to co- LOUIS CONB'I'AN'I'IN. m

operatewiththesecondandthirdpointersaoss

